1) Field of the Invention
The present invention relates to a truss for a vehicle chassis and, more particularly, to a chassis for large vehicles having an opening in one of their lateral sides. It also relates to a method to reinforce a vehicle chassis.
2) Description of the Prior Art
Large motorized vehicles, such as recreational vehicles (RVs), motor homes, and busses, have a chassis on which the body and the mechanical workings of the vehicle, such as the suspension, the motor, and the drive train, are mounted.
An important portion of the bending rigidity (or flexural rigidity) of a conventional vehicle chassis is ensured by a lateral structural truss (FIG. 1) mounted above the passenger floor on each lateral side of the vehicle chassis. The lateral structural truss usually consists of a lower beam mounted at the height of the passenger floor and an upper beam mounted parallel to the lower beam and above the latter. The lower and upper beams are connected with diagonal members. Since the entirety of the lateral structural truss is located above the passenger floor level, the payload volume of the storage compartments located below the passenger floor level is not reduced. For most motorized vehicle users, spacious storage compartments are usually a desired characteristic.
However, when an opening is created in one of the lateral walls of the vehicle, above the passenger floor, to insert a door, a slide-out compartment and the like, the lateral structure of the vehicle chassis is cut. To maintain the bending rigidity of the vehicle chassis despite the discontinuity of the lateral structural truss, a reinforcing truss is added to the vehicle chassis below the opening. Usually, the reinforcing truss consists of a lower beam and an upper beam connected with diagonal members and is mounted below the passenger floor of the vehicle (FIG. 2) in the storage compartments. In that position, the reinforcing truss considerably reduces the available spacing in the storage compartments and their accessibility. Moreover, this reinforcing truss can only take the stresses applied on the vehicle chassis in a static mode, i.e. when the vehicle is stationary. To reinforce the vehicle chassis when the vehicle is moving, locking mechanisms are mounted to the lateral structure on each side of the opening. These locking mechanisms are usually cumbersome inside the vehicle and increase the manufacturing costs, the vehicle weight, and the complexity to assemble the vehicle.